Jeroen Valensa

A fuel cell system (1) is provided and includes a fuel cell stack (3) and a heat transfer device (5) adapted to transfer heat from a cathode exhaust stream of the fuel cell stack (3) to water to be provided to a fuel inlet stream.

A cooling system (10) is provided for use with a fuel processing subsystem (12) for reducing a level of carbon monoxide in a reformate flow (14) for a proton exchange membrane fuel cell system (16). The fuel processing subsystem (12) includes first and second preferential oxidizers (18, 20) to oxidize the carbon monoxide carried in the reformate flow. The reformate cooling system (10) includes a coolant flow path (30), a reformate flow path (32), and first, second, third, and fourth heat… Show more

A cooling system (10) is provided for use with a fuel processing subsystem (12) for reducing a level of carbon monoxide in a reformate flow (14) for a proton exchange membrane fuel cell system (16). The fuel processing subsystem (12) includes first and second preferential oxidizers (18, 20) to oxidize the carbon monoxide carried in the reformate flow. The reformate cooling system (10) includes a coolant flow path (30), a reformate flow path (32), and first, second, third, and fourth heat exchanger core portions (34, 36, 38, 40). The core portions (36-40) are arranged in numbered sequence along the reformate flow path (32) with the first and second core portions (34, 36) located upstream of the first preferential oxidizer (18), and the third and fourth core portions (38, 40) located downstream of the first preferential oxidizer (18) and upstream of the second preferential oxidizer (20). The first and second core portions (34, 36) are arranged in numbered sequence along the coolant flow path (30), one of the third and fourth core portions (38, 40) is arranged upstream of the first core portion (34) along the coolant flow path (30), and the other of the third and fourth core portions (38, 40) is arranged downstream of the second core portion along the coolant flow path (30). Show less

An integrated fuel cell unit (10) includes an annular array (12) of fuel cell stacks (14), an annular cathode recuperator (20), an annular anode recuperator (22), a reformer (24), and an anode exhaust cooler (26), all integrated within a common housing structure (28).

A catalytic reactor including a heat exchanger and a method are provided for transferring heat to a coolant and a reaction fluid. The catalytic reactor includes a reaction fluid flow path, a reaction region, and a coolant flow path. A reaction fluid catalytically reacts at a surface area in the reaction region thereby generating heat. The heat is transferred to a coolant and the reaction fluid based on the coolant and reaction fluid convective heat transfer coefficients respectively. In one… Show more

A catalytic reactor including a heat exchanger and a method are provided for transferring heat to a coolant and a reaction fluid. The catalytic reactor includes a reaction fluid flow path, a reaction region, and a coolant flow path. A reaction fluid catalytically reacts at a surface area in the reaction region thereby generating heat. The heat is transferred to a coolant and the reaction fluid based on the coolant and reaction fluid convective heat transfer coefficients respectively. In one embodiment, the ratio of the coolant convective heat transfer coefficient to the reaction fluid heat transfer coefficient is at least 5:1. Show less

A coolant conditioning system is provided for supplying a coolant flow to a fuel processing subsystem. The coolant conditioning system includes a coolant preheater to transfer heat from a reformate flow to the coolant flow, a heater to selectively add heat to the coolant flow in response to the coolant flow dropping below a minimum temperature, at least one outlet flow path to provide a portion of the coolant flow to at least one fuel processing subsystem, and a return flow path to return a… Show more

A coolant conditioning system is provided for supplying a coolant flow to a fuel processing subsystem. The coolant conditioning system includes a coolant preheater to transfer heat from a reformate flow to the coolant flow, a heater to selectively add heat to the coolant flow in response to the coolant flow dropping below a minimum temperature, at least one outlet flow path to provide a portion of the coolant flow to at least one fuel processing subsystem, and a return flow path to return a remainder of the coolant flow to a storage tank. The coolant conditioning system is dynamically controllable to provide a portion of the coolant flow above a minimum temperature to reduce or prevent condensation of the reformate flow in selected components of the fuel processing subsystem that receive the portion of the coolant flow. Show less

An integrated steam reformer/combustor assembly (42) is provided for use in a fuel processor (20) that supplies a steam/fuel feed mix (34) to be reformed in the assembly and a combustor feed (40) to be combusted in the assembly (42). The assembly (42) includes a housing (44,58) defining first and second axially extending, concentric annular passages in heat transfer relation to each other; a first convoluted fin (46) located in the first passage to direct the feed mix therethrough, the first… Show more

An integrated steam reformer/combustor assembly (42) is provided for use in a fuel processor (20) that supplies a steam/fuel feed mix (34) to be reformed in the assembly and a combustor feed (40) to be combusted in the assembly (42). The assembly (42) includes a housing (44,58) defining first and second axially extending, concentric annular passages in heat transfer relation to each other; a first convoluted fin (46) located in the first passage to direct the feed mix therethrough, the first convoluted fin coated with a catalyst that induces a desired reaction in the feed mix; and a second convoluted fin (50) located in the second passage to direct the combustor feed therethrough, the second convoluted fin coated with a catalyst that induces a desired reaction in the combustor feed. Show less

A combustor preheater (94) is provided for use in a fuel processor (20) to preheat a combustor feed (40) by transferring heat from a post water-gas shift reformate flow (32) to the combustor feed (40). The combustor preheater (94) includes a housing (92) defining first and second axially extending, concentric annular passages in heat transfer relation to each other; a first convoluted fin (96) located in the first passage to direct the post water-gas shift reformate flow (32) therethrough and a… Show more

A combustor preheater (94) is provided for use in a fuel processor (20) to preheat a combustor feed (40) by transferring heat from a post water-gas shift reformate flow (32) to the combustor feed (40). The combustor preheater (94) includes a housing (92) defining first and second axially extending, concentric annular passages in heat transfer relation to each other; a first convoluted fin (96) located in the first passage to direct the post water-gas shift reformate flow (32) therethrough and a second convoluted fin (98) located in the second passage to direct the combustor feed therethrough. Show less

A recuperative heat exchanger (36) is provided for use in a fuel processor (20), the heat exchanger (36) transferring heat from a fluid flow (34) at one stage of a fuel processing operation to the fluid flow (32) at another stage of the fuel processing operation. The heat exchanger (36) includes a housing (56) defining first and second axially extending, concentric annular passages in heat transfer relation to each other; a first convoluted fin (70) located in the first passage to direct the… Show more

A recuperative heat exchanger (36) is provided for use in a fuel processor (20), the heat exchanger (36) transferring heat from a fluid flow (34) at one stage of a fuel processing operation to the fluid flow (32) at another stage of the fuel processing operation. The heat exchanger (36) includes a housing (56) defining first and second axially extending, concentric annular passages in heat transfer relation to each other; a first convoluted fin (70) located in the first passage to direct the fluid flow therethrough; and a second convoluted fin (72) located in the second passage to direct the fluid flow therethrough. Show less

A fuel processing system is provided wherein heat is transferred from a reformate flow (32) downstream from a water-gas shift (38) to both a) a combustor feed flow (40) that is supplied to a combustor (25); and b) a water flow (26) that is supplied to a reformer feed mix (34) for a steam reformer (28).

A cooling system (10) is provided for use with a fuel processing subsystem (12) for reducing a level of carbon monoxide in a reformate flow (14) for a proton exchange membrane fuel cell system (16). The fuel processing subsystem (12) includes first and second preferential oxidizers (18, 20) to oxidize the carbon monoxide carried in the reformate flow. The reformate cooling system (10) includes a coolant flow path (30), a reformate flow path (32), and first, second, third, and fourth heat… Show more

A cooling system (10) is provided for use with a fuel processing subsystem (12) for reducing a level of carbon monoxide in a reformate flow (14) for a proton exchange membrane fuel cell system (16). The fuel processing subsystem (12) includes first and second preferential oxidizers (18, 20) to oxidize the carbon monoxide carried in the reformate flow. The reformate cooling system (10) includes a coolant flow path (30), a reformate flow path (32), and first, second, third, and fourth heat exchanger core portions (34, 36, 38, 40). The core portions (36–40) are arranged in numbered sequence along the reformate flow path (32) with the first and second core portions (34, 36) located upstream of the first preferential oxidizer (18), and the third and fourth core portions (38, 40) located downstream of the first preferential oxidizer (18) and upstream of the second preferential oxidizer (20). The first and second core portions (34, 36) are arranged in numbered sequence along the coolant flow path (30), one of the third and fourth core portions (38, 40) is arranged upstream of the first core portion (34) along the coolant flow path (30), and the other of the third and fourth core portions (38, 40) is arranged downstream of the second core portion along the coolant flow path (30). Show less

A heat exchanger is provided for transferring heat between a first fluid flow and a second fluid flow. The heat exchanger includes a first fluid flow path having a major dimension and a minor dimension and a second fluid flow including at least two flat tubes each having a major dimension and a minor dimension. Each of the flat tubes have at least two passes. Each tube has a transition region joining adjacent passes. Each transition region extends beyond the first fluid flow path major… Show more

A heat exchanger is provided for transferring heat between a first fluid flow and a second fluid flow. The heat exchanger includes a first fluid flow path having a major dimension and a minor dimension and a second fluid flow including at least two flat tubes each having a major dimension and a minor dimension. Each of the flat tubes have at least two passes. Each tube has a transition region joining adjacent passes. Each transition region extends beyond the first fluid flow path major dimension. Show less

A heat exchanger (50) is provided for transferring heat between first and second fluids (52) and (54) having a maximum operating mass flow rate through the heat exchanger (50) and mass flow rates that are substantially proportional to each other. The heat exchanger (50) provides essentially constant outlet temperatures for the first and second fluids (52,54) for all of the flow rates within the operating spectrum of the heat exchanger (50) without the use of an active control system. The heat… Show more

A heat exchanger (50) is provided for transferring heat between first and second fluids (52) and (54) having a maximum operating mass flow rate through the heat exchanger (50) and mass flow rates that are substantially proportional to each other. The heat exchanger (50) provides essentially constant outlet temperatures for the first and second fluids (52,54) for all of the flow rates within the operating spectrum of the heat exchanger (50) without the use of an active control system. The heat exchanger (50) is of particular use in the fuel processing system (36) of proton exchange membrane type fuel cell systems. Show less

Large thermal stresses are avoided and the fuel charge reduced in a vaporizer particularly suited for use in a reformer type fuel cell system and having a construction that includes alternating fuel/water flow path defining cells (68) and hot gas flow path cells (69) by providing heat transfer augmentation, such as a lanced and offset fin (120), only in that part of the gas flow path structure (69) adjacent the regions in the fuel/water flow path cells (68) where heating of the liquid… Show more

Large thermal stresses are avoided and the fuel charge reduced in a vaporizer particularly suited for use in a reformer type fuel cell system and having a construction that includes alternating fuel/water flow path defining cells (68) and hot gas flow path cells (69) by providing heat transfer augmentation, such as a lanced and offset fin (120), only in that part of the gas flow path structure (69) adjacent the regions in the fuel/water flow path cells (68) where heating of the liquid fuel/water and vaporizing of the fuel/water where the mixture exists is a two phase material occurs and not in the area adjacent those parts of the fuel/water flow path structure (68) in which superheating of the vaporized fuel/water mixture is occurring. Show less

An evaporative heat exchanger (10) is provided for the transfer of heat to a first fluid (30) from a second fluid (28) and a third fluid (22) to vaporize the first fluid (30). The heat exchanger (10) includes a core (40), a first flow path (60) in the core for the first fluid (30), a second flow path (66) in the core (40) for the second fluid (28), and a third flow path (68) in the core (40) for the third fluid (22). The core (40) includes a first section (42), a second section (44), and a… Show more

An evaporative heat exchanger (10) is provided for the transfer of heat to a first fluid (30) from a second fluid (28) and a third fluid (22) to vaporize the first fluid (30). The heat exchanger (10) includes a core (40), a first flow path (60) in the core for the first fluid (30), a second flow path (66) in the core (40) for the second fluid (28), and a third flow path (68) in the core (40) for the third fluid (22). The core (40) includes a first section (42), a second section (44), and a third section (46), with the second section (44) connecting the first and third sections (42, 46). The first flow path (60) extends through all of the sections (42, 44, 46), the second flow path (66) extends through the first section (42), and the third flow path (68) extends through the third section (46). Show less

A fluid flow distribution device (10) is provided for use in a heat exchanger (12) having multiple heat exchange units (14) that receive a fluid flow (18) from an fluid inlet (16). The device includes a plurality of tortuous flow paths (31) to direct distributed portions of the fluid flow (18) from the inlet (16) to the heat exchange units (14). Each tortuous flow path (31) is defined by a pair of flow chamber plates (24,26), and an orifice plate (28) sandwiched between the flow chamber plates… Show more

A fluid flow distribution device (10) is provided for use in a heat exchanger (12) having multiple heat exchange units (14) that receive a fluid flow (18) from an fluid inlet (16). The device includes a plurality of tortuous flow paths (31) to direct distributed portions of the fluid flow (18) from the inlet (16) to the heat exchange units (14). Each tortuous flow path (31) is defined by a pair of flow chamber plates (24,26), and an orifice plate (28) sandwiched between the flow chamber plates (24,26). Each tortuous flow path (31) includes a series (34) of orifices (36) extending through the orifice plate (28), a first pattern (38) of first flow chambers (40) formed in one of the flow chamber plates (24,26) and aligned with sequential pairs of the orifices (36), and a second pattern (42) of second flow chambers (44) formed in the other of the flow chamber plates (24,26) and offset with respect to the first pattern (38) and the pairs of orifices (36). Show less

An electronic device/heat sink assembly having at least first and second heat generating electronic devices, a heat sink member, a resilient integral spring clip, the clip including a base member and first and second oppositely facing resilient leg members extending from opposite ends of the base member, the heat sink member having oppositely facing first and second surfaces, a separate one of the electronic devices positioned on each of the first and second sink surfaces, the clip dimensioned… Show more

An electronic device/heat sink assembly having at least first and second heat generating electronic devices, a heat sink member, a resilient integral spring clip, the clip including a base member and first and second oppositely facing resilient leg members extending from opposite ends of the base member, the heat sink member having oppositely facing first and second surfaces, a separate one of the electronic devices positioned on each of the first and second sink surfaces, the clip dimensioned and positioned such that the leg members sandwich the devices and heat sink therebetween. Show less